Since it was surprised by the large demonstration on 15 June, the Iranian Government's strategy --- haphazard at first, much more systematic in the last week --- has been to constrict the life out of the opposition, promising a token but lengthy vote recount, shutting down media coverage, detaining hundreds, and preventing any mass gatherings.

There is a growing sense, both among supporters of the regime and some in the opposition, that the strategy is working. The opposition's demonstrations were beaten down on Wednesday and blocked on Thursday, and the only hint of a public show today is the release of green balloons at 1 p.m. local time (0830 GMT). That leaves the public arena free for the Supreme Leader, as he leads prayers at Tehran University.

My speculaton is that Ayatollah Khomeini will speak from a platform of victory, to the acclaim of the worshipers. He will praise Iran's fortitude in the face of Western intervention and again extol its superior democracy. Again calling for order, he will offer a very limited reconciliation to the opposition, speaking of the Guardian Council's acknowledgement of concerns over the vote while condemning the "extremists" in the movement.

Watch, however, for the Supreme Leader's references (or lack of references) to Mahmoud Ahmadinejad. It has yet to dawn on many observers of the crisis, but the President will come out of this conflict badly even if the regime succeeds. His "legitimacy" has depended upon Khamenei's backing; Ahmadinejad has done little since his initial post-election celebration except to criticise President Obama on Wednesday. Behind-the-scene manoeuvres by clerics and politicians like former President Hashemi Rafsanjani have highlighted Ahmadinejad's weakness.

Best guess: just like last week, Khamenei will balance public support for the President with some words, possibly coded, to acknowledge the continuing relevance of Ahmadinejad's foes.

The highest-profile sign of opposition on Thursday was Mir Hosssein Mousavi's letter urging supporters to continue their demonstrations, but with restraint. The statement has gotten some notice outside Iran, especially in CNN's coverage, but it is unclear --- given the Government's limiting of communications --- how far the statement has circulated within the country.

It appears the widespread detentions have crippled the protests by shutting away both key organisers and communicators, from youth leaders to editors-in-chief.